SDN Powers AT&T's Rapid On-Demand Expansion

AT&T has been able to rapidly expand its Network on Demand service, today announcing 100 new cities where it's available, based on widespread deployment of an SDN-based control layer and creation of APIs to link its existing operations and business support systems to its web-based customer interface. The rapid expansion of the new capability, which lets customers see their Switched Ethernet network topology and easily order, manage and change services, is an example of what SDN can enable. (See AT&T Expands Network on Demand to 100 Cities.)

"When we went from one city to six, in February, we could have gone to 100, but we felt it would be good to learn incrementally, and not just about what technical wrinkles may occur," Goodell tells Light Reading in an interview. "We also had to develop the fundamentals of communicating and channel engagement and speaking externally about this. All of these are things we are thinking about. The control layer has been in place -- we are now at a point that we can expand it across our 21-state footprint."

The hardest part of the process was developing more than 200 applications programming interfaces that went northbound to the web interface used by customers to order, manage and change their Switched Ethernet services, and southbound to the AT&T network, he admits. Because of AT&T's extensive legacy network, the carrier faced complications that a green-field deployment of SDN would not have faced.

"One of the things that is unique is that we are doing this at a scale that has never been done before," Goodell says. "There are surprises every day -- that's part of the blessing of being on the bleeding edge of something that is this significant. There have been a lot of issues but that's part of the challenge and one of the things I love, that we are doing all of this on top of an existing network."

The guiding principle of the process has been to keep things simple for the customer, to hide the complexity of legacy systems and focus on extracting what customers need, and to keeping the look and feel of the existing AT&T Switched Ethernet service for the customers, Goodell says. "We have been very methodical about that, as we have layered on additional functionality."

Want to know more about AT&T's plans for SDN and NFV? Hear Andre Fuetsch, senior vice president, Architecture & Design, deliver a keynote address at Light Reading's second Big Telecom Event on June 9-10 in Chicago. Get yourself registered today or get left behind!

Pilot customers, including IBM Corp. (NYSE: IBM), have provided valuable feedback along the way, and one of the things that has proven most helpful to them is viewing their own network topology on the web interface, and having the ability to make rapid changes, he comments. Four major commercial deals have been landed based on Network on Demand.

Business users "can see exactly what their network looks like," Goodell explains. "They can see all the end points and the way the network is logically configured. It's very simple and intuitive. That capability hasn't existed anywhere within AT&T outside of Network on Demand."

The customer interface has been designed by AT&T's Digital Experience team, led by Laura Merling, who also has that responsibility for AT&T Mobility, Small Business, and Enterprise customers. They bring expertise to bear in creating the new web interface so that it has the look and feel of existing AT&T products and that continuity, Goodell says. "These are pieces of the puzzle that haven't been there before."

The interface and the service itself will continue to evolve, Goodell says. One major step forward with this expansion is the ability to manage both SDN-controlled and non-SDN controlled elements in a hybrid network. Ahead lies the expansion into Layer 3 services, which will be added to the Switched Ethernet capabilities, and virtualized network functions, which will also be added at the edge of AT&T's network and at the customer premises as well.

"We see Switched Ethernet as a foundational service," Goodell says. "And we intend to layer more things on top of it."

Re: Real-world SDN AT&Ts On-Demand is an enhanced software conguration/re-configuration system which has nothing to do with SDN as defined by either the Open Networking Foundation (OpenFlow model) or VMWare/Nicera (Network Virtualization model). It doesn't involve separation of Control & Data Planes and shouldn't because provisioning/configuration/reconfiguration doesn't occur during information transfer between network nodes. Nor does it map a logical network onto a physical network as Network Virtualization does.

Similarly, AT&T's SDN WAN-AKA NetBond- is a great way for enterprise customers using AT&T's IP-MPLS VPN to reach different Cloud Service Providers, but it also doesn't fit any definition or model of SDN. Instead, NetBond uses proprietary routing protocols for dynamic route optimization over it's IP-MPLS VPN. It's comprehensively described in this post: